The 42-year-old welcomed daughter Coco with ex-wife Courteney Cox in June 2004, and could not be more excited for his second child.

"I’ve done it once," he told Us. "It’s all new, but it’s all beautiful."

Arquette says he's excited for, "playing catch, making [his son] laugh, and seeing my girlfriend Christina being a mother for the first time and all the joy and love that it’s going to bring her and me."